A 66 block is a punchdown block containing rows of four IDC style clips. It is used for terminating 22-26 AWG solid copper cross-connect station wiring for many types of phone systems. Bridge clips are required to complete the circuit between the left and right side of the 66 block. * Dimensions: 10' (L) x 2.5"" (W) x 1.5"" (H) * 50 pairs 66 wiring block